Seth is mentally incompetent but has not been adjudged by a court to be incompetent. Seth enters into a contract with Toby for the cleaning and maintenance of Seth's warehouse. Most likely, the contract is

a$.$ void.

b$.$ enforceable if Toby did not know that Seth was mentally incompetent.

c$.$ enforceable if the warehouse needs cleaning and maintenance.

d$.$ voidable if Seth did not comprehend the consequences.